Corner sander



Oct. 18, 1966 A. E. NELSON CORNER SANDER Filed Dec. 5, 1963 3,279,130 CORNER SANDER Arthur E. Nelson, ()xnard, Calif., assiguor to Neeco Tools, Inc., a corporation of California Filed Dec. 5, 1963, Ser. No. 328,218 3 Claims. (Cl. 51390) This invention relates generally to sanding apparatus and more particularly, to an improved sanding device for finishing dry plaster wall corners after application of taping thereto.

In dry plaster wall construction, panels of preformed plaster are positioned against the studding or other structure forming the frame work of the wall. At adjacent portions of the panels, the cracks are covered by special tape with a suitable adhesive. Similarly, the corners are taped, the tape itself being bent longitudinally along a midline with half of the tape adhering to one wall adjacent the corner and the other half adhering to the other wall.

The adhesive material itself tends to exude from the edges of the tape. Also, foreign matter and dirt often cling to the adhesive portion of the tape or to the tape itself. It is therefore common practice to sand lightly the various joints of the panels at the points where tape has been applied. There is generally no problem encountered whan sanding joints formed by coplanar panels since a flat surface sander is all that is necessary. However, in the case of corners, it is difficult to remove foreign matter in the corner line or apex of the corner. Such prior art sanders as have been available generally include two surfaces forming an outer angle with respect to each other of approximately 270 degrees. However, while these surfaces will clean the outer edges of the corner tape, they are not effective in finishing the central bent portion of the tape within the corner line. One reason for this difficulty with conventional corner sanders is the fact that the walls may form an angle slightly less than 90 degrees in which event, the apex portion of the sander will be spaced from the corner line formed by the walls. Also, the sandpaper tends to form a small radius at the corner of the sander and thus will not effectively reach the corner line.

With the foregoing in mind, it is a primary object of this invention to provide a greatly improved corner sander in which the foregoing problems are overcome.

More particularly, it is an object to provide a corner sander of novel construction such that a corner tape itself is not only urged directly into the corner line but any foreign matter or undesirable adhesive remaining thereon is removed.

Another object is to provide a corner sander in which the edges of the tape adjacent to the corner line are cleaned simultaneously with the cleaning of the corner line.

Still another important object is to provide a corner sander in which the sandpaper employed may be very easily removed and replaced without the necessity of special tools.

Another object is to provide a corner sander which is adapted to conform to and follow a corner wall portion when moved over large distances.

Another object is to provide a corner sander which will also serve as a conventional fiat sander.

Briefly, these and other objects and advantages of this invention are attained by providing a corner sander in the form of an integral plate structure including two outside surfaces at an angle of ubstantially 2.70 degrees with respect to each other. In accordance with an essential feature of this invention, the apex portion of the surfaces is defined by a protuberance substantially bisecting this out- United States Patent er angle. This protuberance extends over the length of the outer surfaces and serves to engage the corner line of a wall corner when sandpaper is wrapped around the integral plate structure to more effectively remove any undesired foreign matter or mud particles.

In a preferred embodiment of the invention, there is provided a universal mounting for securing a handle means to the rear of the integral plate structure so that the plate structure may readily remain in surface engagement with the wall corner when moved up and down over relatively large distances.

Suitable cushioning pads cover the outer surfaces to cushion the main portions of the sandpaper when engaging the tape and unique clamp plates are used for attaching and removing of the sandpaper.

A better understanding of the invention will now be had by referring to a preferred embodiment thereof as illustrated in the accompanying drawings, in which:

FIGURE 1 is a perspective view of a wall corner and the corner sander of this invention in position for use; and,

FIGURE 2 is a plan cross-section of the corner sander of FIGURE 1.

Referring first to FIGURE 1, there are illustrated dry plaster type walls 10 and 11 meeting to form a corner line 12. A corner tape 13 is shown covering the corner 12 and after being placed, there will generally be some adhesive A exuding from the outside edges 14 and 15 of the tape.

To remove this excess adhesive and clean the tape 13 of excess mud or foreign particles, the unique sander of this invention is employed. This sander, as shown in both FIGURES l and 2, includes an integral plate structure 17 defining two front flat surfaces 18 and 19 disposed at an outside angle of substantially 270 degrees with respect to each other. As shown in both FIGURES l and 2, the apex portion of the surfaces is defined by an elongated pr-otuberance 20 directed outwardly in a direction substantially bisecting the 270 degree angle.

In the preferred embodiment, the surfaces 18 and 19 are covered with resilient pads 21 and 22 and sandpaper 23 is then wrapped about the structure to pass over the pads and the protuberance 20 as shown. The ends of the sandpaper may be secured to the outer rear surfaces of the plate structure 17 by suitable clamp members 24 and 25 threadedly secured to the plate structure as by screw means 26 and 27. These screws may have knurled heads to facilitate manual removal and replacement.

The corner sander itself is held by means of a central horizontal shaft 28 to which is rotatably mounted a universal mounting 29 supporting a handle 30 projecting rear-wardly from the structure. With this arrangement, a person holding the handle may move the plate structure up and down a corner wall with the angle of the handle varying as the height above the floor of the sander changes.

In operation, the sandpaper 23 is sandwiched between the clamps 24- and 25 as described after being positioned to pass over the pads 21 and 22 and protuberance 20. The knobs 26 and 27 are tightened to effect a. secure clamp force on the sandpaper.

The integral plate structure may then be pressed into the corner 16 formed by the tape 13 as illustrated in FIGURE 1 to effectively clean mud or foreign matter adhering unevenly to the tape 13 or edges 14 and 15 thereof. The relatively large width of the outer surfaces 18 and 19 will effect simultaneous sanding of the edges 14 and 15 of the tape, any slight unevenness in the walls being accommodated by the resilient pads 21 and 22. Also, the protuberance 20 will ensure that the central portion of the sandpaper is urged into the corner line 16 of the tape so that foreign matter will be removed therefrom.

If desired, only one exterior surface such as the surface 19 together with the pad 22 and sandpaper portion passing thereover can be used to perform conventional flat sanding.

After the sandpaper 23 has been worn, it is a simple matter to manually unthread the knobs 26 and 27, remove the plates 24 and 25, and unwrap the sandpaper 23. A new piece of sandpaper may then be substituted and the plates 24 and 25 replaced.

The instant invention has proved highly successful in effecting corner sanding, the protuberance itself serving a unique function in properly cleaning the tape at the corner line of the walls and also removing foreign matter therefrom at the same time that excess adhesive is removed from the edges of the tape.

While only one particular embodiment of the invention has been set forth and described, various changes that fall clearly within the scope and spirit of the invention will occur to those skilled in the art. The corner sander is therefore not to be thought of as limited to the exact construction shown merely for illustrative purposes.

What is claimed is:

l. A corner sander comprising, in combination: an integral plate structure defining two flat surfaces forming an outside angle of substantially 270, said surfaces meeting at an apex comprising an elongated rigid protuberance directed outwardly from said surfaces in a direction bisecting said angle and adapted to be urged into a wall corner with said surfaces in substantially parallel relationship to the walls defining said corner respectively; resilient pad means fixed to said surfaces on either side of said protuberance; and a sheet of sandpaper secured to said plate structure to pass about said pads and said protuberance, whereby said protuberance urges the portion of said sandpaper passing thereover into said corner of said wall while the remaining portions of said sandpaper engage the wall areas adjacent to said corner.

2. A sander according to claim 1, including a handle; and a universal mounting coupling said handle to a rear portion of said sander.

3. A sander according to claim 2, including clamp members adapted to engage the rear portions of said surfaces adjacent their outer edges to sandwich the outer edges of said sandpaper therebetween; and screw means for clamping said clamp members against said plate structure to secure said sandpaper thereto.

References Cited by the Examiner UNITED STATES PATENTS 2,817,931 12/ 1957 Houser 51-393 X FOREIGN PATENTS 26,424 12/ 1904 Great Britain.

LESTER M. SWINGLE, Primary Examiner. ROBERT C. RIORDON, Examiner.

L. S. SELMAN, Assistant Examiner. 

1. A CORNER SANDER COMPRISING, IN COMBINATION: AN INTEGRAL PLATE STRUCTURE DEFINING TWO FLAT SURFACES FORMING AN OUTSIDE ANGLE OF SUBSTANTIALLY 270*, SAID SURFACES FORMING ING AT AN APEX COMPRISING AN ELONGATED RIGID PROTUBERANCE DIRECTED OUTWARDLY FROM SAID SURFACES IN A DIRECTION BISECTING SAID ANGLE AND ADAPTED TO BE URGED INTO A WALL CORNER WITH SAID SURFACES IN SUBSTANTIALLY PARALLEL RELATIONSHIP TO THE WALLS DEFINING SAID CORNER RESPECTIVELY; RESILIENT PAD MEANS FIXED TO SAID SURFACES ON EITHER SIDE OF SAID PROTUBERANCE; AND A SHEET OF SANDPAPER SECURED TO SAID PLATE STRUCTURE TO PASS ABOUT SAID PADS AND SAID PROTUBERANCE, WHEREBY SAID PROTUBERANCE URGES THE PORTION OF SAID SANDPAPER PASSING THEREOVER INTO SAID CORNER OF SAID WALL WHILE THE REMAINING PORTIONS OF SAID SANDPAPER ENGAGE THE WALL AREAS ADJACENT TO SAID CORNER. 